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Rat respiratory coronavirus infection: replication in airway and alveolar epithelial cells and the innate immune response.

ABSTRACT: The rat coronavirus sialodacryoadenitis virus (SDAV) causes respiratory infection and provides a system for investigating respiratory coronaviruses in a natural host. A viral suspension in the form of a microspray aerosol was delivered by intratracheal instillation into the distal lung of 6-8-week-old Fischer 344 rats. SDAV inoculation produced a 7 % body weight loss over a 5 day period that was followed by recovery over the next 7 days. SDAV caused focal lesions in the lung, which were most severe on day 4 post-inoculation (p.i.). Immunofluorescent staining showed that four cell types supported SDAV virus replication in the lower respiratory tract, namely Clara cells, ciliated cells in the bronchial airway and alveolar type I and type II cells in the lung parenchyma. In bronchial alveolar lavage fluid (BALF) a neutrophil influx increased the population of neutrophils to 45 % compared with 6 % of the cells in control samples on day 2 after mock inoculation. Virus infection induced an increase in surfactant protein SP-D levels in BALF of infected rats on days 4 and 8 p.i. that subsided by day 12. The concentrations of chemokines MCP-1, LIX and CINC-1 in BALF increased on day 4 p.i., but returned to control levels by day 8. Intratracheal instillation of rats with SDAV coronavirus caused an acute, self-limited infection that is a useful model for studying the early events of the innate immune response to respiratory coronavirus infections in lungs of the natural virus host.

SUBMITTER: Funk CJ

PROVIDER: S-EPMC2887555 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

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Rat respiratory coronavirus infection: replication in airway and alveolar epithelial cells and the innate immune response.

Funk C Joel CJ Manzer Rizwan R Miura Tanya A TA Groshong Steve D SD Ito Yoko Y Travanty Emily A EA Leete Jennifer J Holmes Kathryn V KV Mason Robert J RJ

The Journal of general virology 20090909 Pt 12

The rat coronavirus sialodacryoadenitis virus (SDAV) causes respiratory infection and provides a system for investigating respiratory coronaviruses in a natural host. A viral suspension in the form of a microspray aerosol was delivered by intratracheal instillation into the distal lung of 6-8-week-old Fischer 344 rats. SDAV inoculation produced a 7 % body weight loss over a 5 day period that was followed by recovery over the next 7 days. SDAV caused focal lesions in the lung, which were most sev ...[more]

PMID: 19741068

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Dataset Information

Rat respiratory coronavirus infection: replication in airway and alveolar epithelial cells and the innate immune response.

Publications

Rat respiratory coronavirus infection: replication in airway and alveolar epithelial cells and the innate immune response.

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